Meteorology
5.09 METARs
References:
FTGU pages 160-163
AWWS: www.flightplanning.navcanada.ca
5.09 METARs
• MTPs:
– Weather Observing Stations
– METARs
Weather Observing Stations
• Weather observation are taken every hour at
selected aerodromes throughout Canada and
U.S.A.
• These observations are taken by trained
observers or by an automatic weather station;
• The Automated Weather Observation System
(AWOS) is designed to electronically collect
weather data and to disseminate partial or full
surface weather observations;
• 2 types- METARs and TAFs
METARs
• METAR: hourly weather report (issued on
the hour); and
• SPECI: special weather observations
issued at times other than on the hour, as
a result of a significant weather change.
METAR CYQQ 201400Z 00000KT 20SM BKN025 BKN160 06/05 A3006
RMK SC3AC1 SLP179=
SPECI CYKF 201347Z AUTO 19011KT 9SM SCT008 BKN015 OVC021
09/ A2919 RMK MAX WND 21016KT AT 1305Z=
METARs
Airport Identifier
• INTERNATIONAL - 4 LETTERS
EXAMPLE
CYWG Winnipeg
(C – Canadian airport)
KSEA
EDDT
NZOA
(K – American airport)
Seattle, USA
Berlin, Germany
Omarama, New Zealand
METAR CYQQ 201400Z 00000KT 20SM BKN025 BKN160 06/05 A3006
RMK SC3AC1 SLP179=
SPECI CYKF 201347Z AUTO 19011KT 9SM SCT008 BKN015 OVC021
09/ A2919 RMK MAX WND 21016KT AT 1305Z=
METARs
Date and Time
• the date and time of the observation are always given in six digits,
using universal coordinated time (UTC);
201400Z  20th day at 1400 (2pm) Zulu
201347Z  20th day at 1327 (1:37pm) Zulu
Note: In BC, there is a 7 hour (daylight saving time) difference between
pacific time and zulu time . Therefore 1400 is 0700.
METAR CYQQ 201400Z 00000KT 20SM BKN025 BKN160 06/05 A3006
RMK SC3AC1 SLP179=
SPECI CYKF 201347Z AUTO 19011KT 9SM SCT008 BKN015 OVC021
09/ A2919 RMK MAX WND 21016KT AT 1305Z=
METARs
Surface Winds
• Wind Direction - degrees true, always 3 digits to the nearest 10
degrees.
• If direction varies 60° or more and the mean speed exceeds 3
KTs, during the 10 minute period preceding the observation, it is
reported 3 digits, the letter “V” and 3 more digits”
00000KT  000 degrees T at 00 KT
AUTO 19011G20KT  Automated observation, 190 degrees T at 11
KT gusting to 20 KT
METAR CYQQ 201400Z 00000KT 20SM BKN025 BKN160 06/05 A3006
RMK SC3AC1 SLP179=
SPECI CYKF 201347Z AUTO 19011G20KT 9SM SCT008 BKN015
OVC021 09/ A2919 RMK MAX WND 21016KT AT 1305Z=
METARs
Prevailing Visibility
• Is the greatest visibility common to 1/2 or more of the
horizontal circle (observation point);
• reported in statute miles and fractions
2 1/2SM  2.5 statute miles
9SM  9 statute miles
METAR CYQQ 201400Z 00000KT 2 1/2SM SCT004 BKN025 BKN160
06/05 A3006 RMK SC3AC1 SLP179=
SPECI CYKF 201347Z AUTO 19011G20KT 9SM SCT008 BKN015
OVC021 09/ A2919 RMK MAX WND 21016KT AT 1305Z=
METARs
Runway Visual Range
RVR – reported whenever prevailing visibility is 1 mile or less and/or the
RVR is indicating 6,000 ft or less (10 minute average)
R36L/4000FT/D  Runway 36 left has a visual range of 4000 feet and
the trend is decreasing
R06/3000FT/U  Runway 06 has a visual range of 3000 feet and the
trend is upward
METAR CYWG 132000Z 30015 3/4SM R36L/4000FT/D SCT004 BKN025
BKN160 06/05 A3006 RMK SC3AC1 SLP179=
SPECI CYKF 201347Z AUTO 19011G20KT 3/4SM R06/3000FT SCT008
BKN015 OVC021 09/ A2919 RMK MAX WND 21016KT AT 1305Z=
METARs
Present Weather
Present weather is comprised of weather phenomena (precipitation,
obscuration, or other phenomena) preceded by one or two
qualifiers (intensity or proximity to the station and descriptor)
Intensity modifier
“-” for “light”
No modifier “moderate”
“+” for “heavy”
+
Type of Weather
SN (snow)
RA (rain)
FG (fog)
METAR CYWG 132000Z 30015 3/4SM -RA SCT004 BKN025
BKN160 06/05 A3006 RMK SC3AC1 SLP179=
METARs
Weather Abbreviations
• DESCRIPTORS
SH SHOWERS
BL BLOWING
MI SHALLOW
PR PARTIAL
FZ FREEZING
DR LOW DRIFTING
BC PATCHES
TS THUNDERSTORM
• PRECIPITATION
RA RAIN
DZ DRIZZLE
IC ICE CRYSTALS
PL ICE PELLETS
SN SNOW
SG SNOW GRAINS
GR HAIL
GS SNOW PELLETS
UP UKNOWN
PRECITATION
(AWOS only)
METARs
• OBSCURING
PHENOMENA
HZ HAZE
SA SAND
DU DUST
FU SMOKE
FG FOG (VSBY < 5/8)
BR MIST (VSBY  5/8)
VA VOLCANIC ASH
• OTHER
+FC TORNADO or
WATERSPOUT
FC FUNNEL CLOUD
SS SAND STORM
+SS SAND STORM (VSBY <
5/16)
DS DUSTSTORM
+DS DUSTSTORM (VSBY <
5/16)
SQ SQUALLS
Confirmation
What type of weather is happening?
METAR CYWG 132000Z 30015 3/4SM SHRA SCT004 BKN025 BKN160
06/05 A3006 RMK SC3AC1 SLP179=
SPECI CYKF 201347Z AUTO 19011G20KT 3/4SM -BLSN SCT008
BKN015 OVC021 00/M05 A2919 RMK MAX WND 21016KT AT 1305Z=
METAR CYXU 201600Z 19012G18KT 2SM -RADZ BR BKN005 OVC020
09/08 A2922 RMK SF6SF2 CIG RAG SLP897=
SPECI CYZF 201510Z 29003KT 1 1/2SM -SN VV002 00/ RMK SN8=
METAR CYQQ 041200Z 23018G25 5SM +TSRA BKN009 BKN025
OVC030 15/12 A2899 RMK CB5CB2TCU1=
METARs
Sky Condition
• The sky is divided into 8 segments, each called an okta
• Codes for sky cover amounts are:
SKC…………… Sky clear
FEW ................... Few Trace to 2/8
SCT……………. Scattered 3/8 to 4/8
BKN …………… Broken 5/8 to 7/8
OVC……………. Sky Overcast 8/8
Sky cover amounts are cumulative therefore, layer amounts include
the sum of any layers below.
A cloud ceiling is said to exist when the coverage symbol BKN or
OVC is reported.
METARs
SCT004 BKN025 BKN160  scattered at 400’ AGL, broken at
2500’AGL, broken at 16000’AGL
BKN009 BKN025 OVC030  broken at 900’AGL, overcast at 3000’
FEW100  few at 10000’AGL
If clouds are low, height are given in a vertical visibility height
Ex. VV002  vertical visibility of 200’ AGL
METAR CYWG 132000Z 30015 3/4SM SHRA SCT004 BKN025 BKN160
06/05 A3006 RMK SC3AC1 SLP179=
METAR CYQQ 041200Z 23018G25 5SM +TSRA BKN009 OVC030 15/12
A2899 RMK CB5TCU2=
METARs
Temperature/Dewpoint
• Temperature recorded in degrees Celsius
• “M” signifies a negative temperature
• temperature and dew point are separated by a slash (/)
06/05  Temperature 6 degrees/ dewpoint 5 degrees
M07/M09  Temperature -7 degrees/ dewpoint -9 degrees
METAR CYQQ 201400Z 00000KT 2 1/2SM SCT004 BKN025 BKN160
06/05 A3006 RMK SC3AC1 SLP179=
SPECI CMYKF 201347Z AUTO 19011G20KT 9SM SCT008 BKN015
OVC021 M07/M09 A2919 RMK MAX WND 21016KT AT 1305Z=
METARs
Altimeter Setting
• “A” is the group identifier that indicates altimeter setting
• it is reported in inches of mercury
• Altimeter settings are given in hundredths of an inch of mercury.
A3006  30.06 Inches of mercury (“Hg)
A2919  29.19”Hg
METAR CYQQ 201400Z 00000KT 2 1/2SM SCT004 BKN025 BKN160
06/05 A3006 RMK SC3AC1 SLP179=
SPECI CMYKF 201347Z AUTO 19011G20KT 9SM SCT008 BKN015
OVC021 M07/M09 A2919 RMK MAX WND 21016KT AT 1305Z=
METARs
Remarks- RMK
Includes the following information:
- cloud layer type and opacity in eights of sky concealed
- sea level pressure (SLP) in hectopascal (hPa);
- other weather significant to aviation.
• RMK SC3AC1 SLP179=  Remarks Stratocumulus 3 oktas,
altocumulus 1 okta, sea level pressure 1017.9mb
METAR CYQQ 201400Z 00000KT 2 1/2SM SCT004 BKN025 BKN160
06/05 A3006 RMK SC3AC1 SLP179=
SPECI CMYKF 201347Z AUTO 19011G20KT 9SM SCT008 BKN015
OVC021 M07/M09 A2919 RMK MAX WND 21016KT AT 1305Z=
METARs
• RMK MAX WND 21016KT AT 1305Z SLP 995=
 Remarks: maximum wind is 210 degrees at 16 kt
recorded at 1305Z. Sea level pressure 999.5mb
Note on Sea level pressure:
When the SLP is between 0 and 5 put 10 in front of the
number
SLP162 = 1016.2mb
When the SLP is between 6 and 9 put a 9 in front of the
number
SLP993 = 999.3mb
METARs
Remarks: Cloud abbreviations
The following abbreviations are used for cloud types:
CI
cirrus
ST
stratus
CS
cirrostratus
SF
stratus fractus
CC
cirrocumulus
SC
stratocumulus
AS
altostratus
CU
cumulus
AC
altocumulus
CUFRA cumulus fractus
NS
nimbostratus
TCU towering cumulus
CB
cumulonimbus
ACC altocumulus castellanus
METARs
What else might you see in the remarks?
• “RE” identifies the group weather phenomena that was
observed during the hour since the last METAR but not
at the time of observation.
REFZRA = recent freezing rain
• “WS” identifies wind shear up to 1600’AGL
WS All RWY = wind shear on all runways
WS RWY 20R = wind shear on runway 20 right
Note on METAR: you will see many other abbreviations.
Often add in some vowels and you should be able to
figure out the word
Confirmation
Decode the following:
• METAR CYTR 132000Z 12003KT 2 1/2SM BR
OVC013 03/03 A2982 RMK SC8 SLP023
• METAR CYYZ 132000Z 11003KT 1/8SM
R06/1200FT/D -RADZ FG VV002 04/04 A2976 RMK
FG8 SLP 001
• SPECI CYYZ 132035Z 12006KT 3SMBR OVC008
RMK ST8
• METAR CYYC 021600Z 05008KT 20SM FEW018
BKN057 OVC080 05/01 A2986 RMK SC2SC5AC1
SLP147
Resources
For more practise:
•
Look in the FTGU pg 160-163
•
Check out the aviation weather website
www.flightplanning.navcanada.ca (google AWWS)
Resources
• Type in the airport identifier or search for it
• Then select for it to be in standard METAR language or text.
Do both to help you learn
Resources
Automated Weather
Observation System